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74 BOTANICAL GAZETTE [January 

NOTES FOR STUDENTS. 

Dr. Liugi Buscaglioni suggests the use of "Sudan III" in botanical 
microtechnique. It stains wax, cutin, and suberin intensely red, while cellu- 
lose membranes, collenchyma, gelatinous and lignified membranes remain 
uncolored. Of the cell contents the nucleus, nucleoli, protoplasm, starch 
grains and tannins remain unstained ; while fats, resins, and latex stain bright 
red, and the chloroplasts pale red. — C. R. B. 

Bronislaw Debski 3 finds that during oogenesis in Chara there is no 
reduction in the number of chromosomes. After the breaking down of the 
nuclear membrane, but before the formation of the spindle, protoplasmic 
radiations may be seen around the nuclear cavity. Spindle development was 
not followed in detail, but Debski is inclined to think that it is at first multipolar. 
The cell plate arises from thickenings of the connecting fibers. In the 
nuclei of nearly all mature cells changes occur in the nucleoli and nuclear 
network. These changes lead to fragmentation of the nucleus and such cells 
are no longer capable of division. The cell wall in Characeas shows no cellu- 
lose reaction with chlor-iodide of zinc or with iodine and sulfuric acid. 

In a previous article Debski showed that no reduction in the number of 
chromosomes takes place during spermatogenesis in Chara. — Charles J. 
Chamberlain. 

Parthenogenesis in plants is, to say the least, a very rare phenomenon, 
Chara critiita, species of Saprolegnia, and perhaps Marsilea Drummondii fur- 
nishing the only fairly proven cases among cryptograms. In Cazlebogyne ilici- 
folia, formerly believed to be parthenogenetic, it is now known that the 
embryos developed from nucellar tissues and not from an unfertilized egg. 
Kerner assumed parthenogenesis in Antennaria alfiina because pistillate 
plants developed seed when no staminate plants were in the vicinity. Mer- 
curialis annua is also said to be parthenogenetic. 

H. O. Juel 4 has made a careful survey of the embryology of Antennaria 
alfiina. He reports that generally only pistillate plants are to be obtained, 
and even when staminate plants are found the pollen is either entirely lacking 
or feebly developed. The development of the embryo sac is normal up to 
the eight-celled stage. The antipodals continue to divide and form quite a 
tissue. The polar nuclei do not fuse, but each divides independently and 
contributes to the endosperm, so that, like the egg, they are capable of divi- 
sion without a previous fusion. This seems to be a perfectly proven case of 
parthenogenesis. — Chas. J. Chamberlain. 

3 Weitere Beobachtungen an Chara fragilis. Jahrb. f. wiss. Bot. 32 : 636-670. pi. 
11-12. 1898. 

4 Bot. Centralbl. 74 : 369-372. 1898. 



1899] CURRENT LITERATURE 75 

Items of taxonomic interest are as follows : A good figure of Hyperi- 
cum galioides Lam. has been published in Gardener s Chronicle (III. 24 : 301. 
1898). — Beckwithia is a new genus of Ranunculaceae, described by W. L. 
Jepson {Erythea 6 : 97-99. 1898). The single species, B. Austince, is said to 
be so strikingly like Viola Beckwithii in habit as to have suggested a possible 
teratological form of that species. The affinities of the genus are uncertain, 
suggesting Anemone in general appearance, and Pasonia in its more technical 
characters. The flowers have not been seen. The plant was discovered in 
Modoc county, California. — John W. Harshberger has published {Proc. Philad. 
Acad. 1898 : 372-413) the results of his recent observations upon the Mexican 
flora, made mostly in the Valley of Mexico. A catalogue of species is given, 
with critical notes. — In the current Bull. Torr. Bot. Club (25 : 561-565. 1898) 
George V. Nash has published a revision of Triplasis, a group of grasses 
frequently placed under Triodia. Three species are recognized, T. purpurea, 
T. intermedia (a new species), and T. Americana. In the same journal (580- 
582) A. A. Heller continues his presentation of new and interesting plants 
from western North America, including a new Hydrophyllum from Washing- 
ton. — Janet R. Perkins has published (Engler's bot. Jahrb. 25 : 547-577. 1898) 
some of the results of her investigation of the Monimiaceas. After a discus- 
sion of the general features and taxonomic characters of the group, the 
author presents a synopsis of the Mollinedieae, including ten genera, five of 
which are proposed as new (Macropeplus, Macrotorus, Steganthera, Antho- 
bembix, and Tetrasynandra.) — Under the title " Phycological Memoirs" 
DeAlton Saunders has begun a series of papers in Proc. Calif. Acad. Sci. 
(111.1:147-168. 1898, with 21 lithograph plates). This first contribution 
considers " Some Pacific Coast Ectocarpaceae," and " Sphacelariaceae and 
Encceliaceae of the Pacific Coast." Seven new species of Ectocarptis are 
described, also new species of Sphacelaria, Scytosiphon, and Colpomenia. A. 
new genus of Encceliaceae is described, founded on Punctaria Winstonii 
Ands., and named Halorhipis ("sea-fan") — J. M. C. 

In celebration of the twenty-fifth anniversary of the doctorate of Dr. 
Melchoir Treub, director of the botanical garden at Buitenzorg, the publishers 
of the Annates of the garden have issued a supplement (pp. 167, pi. g) con- 
taining twenty-three short papers prepared by some of those who have been 
accorded the privileges of the garden, both botanists and zoologists. Solms 
Laubach describes the development of the ovule and seed of Rafflesia and 
Brugmansia. Molisch discusses the bleeding of tropical trees in full leaf, the 
pressure in the night often exceeding two atmospheres. Haberlandt describes 
the movements of the leaves of Biophytum, and believes the transmission of 
impulses to be through plasma connections in the cells of the vascular bundles. 
Schiffner establishes a new genus of Hepaticae, Wettsteinia, based on Plagio- 
chila inversa Sande Lac, and Tylimanthus scaber Schiff. Karsten presents 



76 BOTANICAL GAZETTE [JANUARY 

some new researches on the formation of auxospores in diatoms. Goebel 
shows that in all observed Muscineae the wall of the antheridium is active in 
dehiscence, and is not merely ruptured by the swelling contents. Went 
points out a periodicity in the blooming of Dendrobium ; Ewart has a general 
paper on physiological research in the tropics ; Wiesner describes a new form 
of false dichotomy in the shoots of woody plants ; Massart writes on epiphyl- 
lous plants, represented by alga, lichens, hepatics, and mosses. Warburg 
emphasizes the antithesis between the tropical strand flora of America (incl, 
West Africa) and that of Asia (incl. East Africa). Boerlage describes the 
manner of floating and the germination of the fruits of Heritiera littoralis, a 
coast tree of all the Malayan islands. Kamienski describes a new terrestrial 
Utricularia which he dedicates to Treub under the name U. Treubi. Besides 
these there are several other botanical papers of less general interest. — 
C. R. B. 

In a paper just published 5 by Dr. R. H. True and C. G. Hunkel, on the 
poisonous effect exerted on living plants by phenols, the authors summarize 
their results as follows : 

" We find, as far as our knowledge of the dissociation of the phenylic 
compounds permits us to draw conclusions, that, except in isolated instances 
electrolytic dissociation plays but a very subordinate role in determining the 
toxic properties of these substances. Picric and salicylic acids strongly dis- 
sociate and become powerfully poisonous by virtue of the H ions, in great 
measure. Pyrogallol and probably methyl salicylate first undergo other 
molecular changes, after which their products dissociate electrolytically. 
Here the H ions may account for much of the toxic action. In the cresols 
and mono-nitrophenols, electrolytic dissociation seems to exert a pronounced 
influence. Some phenols are comparatively weak in their integrity, but 
quickly change to substances containing constituents even more fatal than H 
ions. Pyrocatechol, and especially hydroquinone, are of this class. 

"Certain radicles seem to have specific properties when introduced into 
the molecule, modifying the toxic value. The number of hydroxyl groups 
(OH) present seems to have little influence on the toxicaction of the phenols, 
as in the series: benzophenol (i OH), resorcinol (2 OH), and phloroglucin 
(3 OH). The introduction of the methyl group (CH 3 ) into the benzene 
nucleus increases the toxicity to a considerable, but rather variable, degree, 
as in the cresols, less plainly in orcinol. The introduction of the isopropyl 
group (CH (CH 3 ) 2 ) into the cresols increases the toxic value of these sub- 
stances, as carvacrol and thymol. The presence of one or more nitro groups 
(N0 2 ) increases the toxic action to a great degree; e.g., mono- and tri- 
nitrophenols. An increase in the number of the N0 2 groups present does not 
seem to increase the toxic action. When the H of an OH group is replaced 

5 Botanisches Centralblatt 76 : — seqq. 1898. 



1 899 ] CURRENT LITER A TURE 7 7 

by a CH 3 group, little influence seems to be exerted on the toxic action, e. g., 
anisol and guaiacol. The carboxyl group (COOH) brings with it a degree of 
toxicity corresponding directly to the degree of dissociation and the number 
of H ions it affords, e. g., salicylic acid." — C. R. B. 

Mr. A. A. Lawson 6 has investigated the earliest stages in the formation 
of the multipolar spindle in the pollen mother-cells of Cobcza scandens. The 
cytoplasm of the resting pollen mother-cell presents a clear uniform appear- 
ance, but as division approaches a zone a granular substance accumulates 
about the nucleus. This zone is so constant in Cobasa and other genera 
examined by the writer that he proposes to designate it by the term fterikary- 
oplasm. The zone was observed in living cells and so could not be regarded 
as an artefact. When the nuclear membrane breaks down, the perikaryo- 
plasm and the linin of the nucleus form a network of kinoplasmic fibers. 
These grow out into several projections and become the cones of the multi- 
polar spindle. Spindle fibers are formed by the elongation of the meshes of 
the network. The cones elongate, become sharp pointed and fuse in two 
groups, thus forming a bipolar spindle. The mature spindle is characterized 
by the great length and crossing of the mantle fibers. Spindle formation in 
the second division of the pollen mother-cells is the same as in the first. No 
centrosomes were observed at any stage of the process. 

Fleming's fluid was used for fixing, and the safranin-gentian violet-orange 
for staining. The reviewer would suggest that while these form a combina- 
tion of unusual value, it would nevertheless be refreshing to find some other 
combination thoroughly perfected, especially since it has been claimed by 
competent observers that mixtures containing chromic acid precipitate certain 
of the liquid albuminoids of the tissues in the form of filaments or networks, 
which are often of great regularity and simulate structural elements of the 
tissues. If this objection is well founded, it applies with especial force to such 
problems as those concerning spindle formation. — Charles J. Chamber- 
lain. 

In an article of some seventy pages, 7 Dr. Georg Klebs gives a detailed 
account of many ingenious and conclusive experiments regarding the nature 
of the sexual and asexual reproductive organs of Sporodinia grandis, and 
the causes which determine their occurrence. 

Of the physical factors, those which heighten transpiration increase the 
tendency to the formation of sporangia. When transpiration is checked, 
within certain limits, the sporangia are partially replaced by zygotes, and 
when transpiration is still further checked, only zygotes are formed. Thus, 
with a relative humidity of 100 per cent, only zygotes are produced ; at 45- 

«Proc. Cal. Acad. Sci. Ill, 1 : 169-184. pi. 33-36. 1898. 

1 Klebs, Georg : — Zur Physiologie der Fortpflanzung einiger Pilze. Jahrbucher 
fiir wiss. Bot. 32 : I. 1898. 



78 BOTANICAL GAZETTE [January 

65 per cent, sporangia only ; below 40 or 42 per cent, the mycelium is sterile. 
But sporangia may be produced in a greater humidity if anything, e. g., a 
current of air, promotes transpiration. 

When the air pressure is reduced to 40 or 6o mm of mercury partheno- 
genesis results; below 2o-25 mm no sex organs are formed, and below i5-20 mm 
no sporangia develop. 

In discussing the food supply it is proved that carbohydrates are needed 
to form zygotes, while sporangia may be formed luxuriantly in nitrogenous 
media. 

It is of interest to note that different isomerous compounds may behave 
differently. Thus maltose provides the food needed for zygote production 
while lactose does not. Unfortunately, stereoisomers were not investigated. 
The minimum concentration in which zygotes could be formed was deter- 
mined ; for this was shown to depend upon the concentration rather than 
upon the absolute quantity of food present. A small quantity of acid salt 
favored zygote building while normal salts and acids retard it. The author 
thinks the favorable substances increase the permeability of the protoplasm 
to nourishment. 

Parthenogenesis in general results when conditions are suited to the pro- 
duction of sex organs and then change so as to restrict their functioning. It 
results with the greatest certainty when the plant grows in a reduced atmos- 
pheric pressure, e.g., about 5o mm . 

As a result of the work, the view of Brefeld, that the determination of the 
kind of organs to be produced comes from within, must be abandoned. Also 
the prevalent notion that zygotes are made in " hard times" finds little sup- 
port, as in nearly every case their formation is more easily arrested than that 
of sporangia. 

Since in luxuriant vegetative growth diminished humidity, permitting trans- 
piration, results in the formation of sporangia, the latter may be regarded as 
shortened branches rendered fertile by the extra supply of nourishment at 
their disposal, or by some as yet unknown stimulus. 

Sporangia and zygotes are morphologically homologous organs, devel- 
oping from aerial hyphae of the same construction. They are similar phys- 
iologically and can develop only in air. The stimulus which calls them forth 
is transpiration, but the optimum for each lies at a different point ; higher for 
sporangia, lower for zygotes. 

The fact that aerial hypha? are subject to a molecular impact different 
from that on the submerged hypha? may be a determining factor in the devel- 
opment of reproductive organs. Also the fact that submerged hypha; may 
absorb nourishment osmotically through a great area while an aerial branch 
receives it through a relatively small cross section may account for some of 
the differences between aerial and submerged parts of fungi, and of higher 
plants as well. — F. L. Stevens.